package com.lfx.fei;

/**
 * @author 李逢喜
 * create 2021/7/15
 */
public class Demo {


    public static int fun(int n){
        if(n<=1) return n;
        return fun(n-2)+fun(n-1);
    }

    public static void main(String[] args) {
        System.out.println(fun(3));
    }
}
